Bilateral Ventricular Papillary Muscle Variations — A Morphometric Study in South Indian Population

BACKGROUND: Papillary muscles (PM) are vital, especially in cases of atrioventricular (AV) valve prolapse. Bilateral and population-specific variations in PM length are among the several factors that influence the failure of AV valve replacement surgeries. PM morphometric variations between ventricles necessitate a thorough understanding of the effective surgical interventions. AIM: This study aimed to measure PM variations in the South Indian population to determine appropriate preventive measures, i.e. to compare PM morphometric parameters in both side heart ventricles and correlate the findings with baseline characteristics. METHODS: This 2-year autopsy-based prospective study involved 171 fresh adult heart samples. The PM was classified by position and measured for length, breadth, and thickness, with the anterior PM being the largest in both. RESULTS: The study outcomes showed statistically significant and consistent differences in the PM dimensions between the left and right ventricles. The left ventricular anterior PM were longer, broader, and thicker than their right ventricular counterparts (P <0.05). The PM morphometric characteristics of the South Indian Population, when compared with the baseline characteristics, showed a significant but variable degree of difference. CONCLUSION: The findings of this study emphasize the importance of considering ventricular-specific PM morphometric data to optimize surgical strategies and prevent treatment failures.